Alcohol consumption leads to a number of behavioral problems, including increased risk of accidents, interpersonal conflict, and risky decision-making. Theory and research point to alcohol's effects on higher-level cognitive processes, as well as effects of the drug on regulation of emotion, as responsible for its behavioral effects. Recent research has shown that alcohol limits the ability to monitor ongoing performance and make adjustments when necessary, manifest as reduced amplitude of scalp-recorded brain potentials associated with the processing of performance errors (i.e., the error-related negativity, or ERN). The current explanation for this effect is that alcohol limits the extent to which errors are detected (i.e., a cognitive effect), leading drinkers to persist in maladaptive behaviors. The objective of the current project is to test the feasibility of a program of research aimed at understanding alcohol-related deficits in performance monitoring and adjustment, as well as other, related phenomena, in terms of the drug's interactive effects on both cognition and affect. Specifically, it is proposed that alcohol reduces the size of cortical error signals not because performance errors go unnoticed following alcohol consumption, but because alcohol reduces the negative affect typically associated with error commission. Two experiments are proposed to test the specific aims of the project, which include (1) testing the error-detection account of alcohol's effects on the ERN against an alternative, affect-modulation account;(2) testing the effects of alcohol on other aspects of performance monitoring reflected in different brain potentials, particularly the error positivity (Pe);(3) testing the effects of alcohol on affective reactions to errors and negative performance feedback;and (4) testing the effects of alcohol on behavioral adjustment as a combined function of impaired error processing and reduced negative affect. Participants in both experiments will be assigned to consume either an alcohol beverage or one of two control beverages prior to completion of a cognitive task requiring quick, forced-choice decisions. Electrophysiological indices of error monitoring and affective reactions will be assessed throughout the experiments using surface electrodes. The first experiment will be a conceptual replication of a recent study in which effects of alcohol on the ERN were demonstrated, but with the addition of a subjective performance accuracy measure accompanying each trial. The second experiment will involve a trial-and-error learning paradigm in which participants must learn appropriate stimulus responses via feedback received after every trial. These experiments together will provide convergent evidence related to the specific aims and overall objective of the project. The outcome of this project will have important implications for understanding why intoxicated individuals often engage and persist in maladaptive behaviors, which could suggest avenues for intervention.